DEO, G P; SHRESTHA, S K; SHRESTHA, I N. Epidural butorphanol for post operative analgesia in lower limb surgeries: A comparative study with epidural tramadol. Journal of Chitwan Medical College, [S. l.], v. 6, n. 3, p. 26–32, 2017. Disponível em: https://www.nepjol.info/index.php/JCMC/article/view/16696. Acesso em: 6 dec. 2025.